<!DOCTYPE html>
<html>
<head>
    <link rel="match" href="inline_block_opacity_change_ref.html">
    <style>
    #a {
        background-color: green;
        display: inline-block;
        width: 1em;
        opacity: 0.2;
    }

    #a.go {
        opacity: 1;
    }
    </style>
</head>

<body>
    <span style="transition: opacity .1s ease-out;" id="a">a</span>
    <script>
            document.body.offsetWidth; // force layout
            document.querySelector('#a').classList.add('go');
    </script>
</body>
</html>
